"It's not me, it's a guy in my club.
He does do kind of at cross/skip/jump step during the run up and uses two fingers together on the inside rim.
I know he can go 460-490 with the side arm when going big, and we calculated the speed to be…"

"I think you need to tuck your elbow in closer to your free floating rib this will give you a much better snap and help you keep a straight level shot which will increase your distance also keep your feet planted the entire stride try a cross step…"